Connect EC2 to DynamoDB

Question

Hi

I cant seem to connect to DynamoDB from my EC2 instance.

I have set up a roll with full access to DynamoDB and applied it to the EC2 instance. I assume any instance in the same account can access the Dynamo table or am I missing a step? There doesn't seem to be much help on the AmazonDynamoDBConfig part.

This is my code in .Net.
```
AmazonDynamoDBConfig clientConfig = new AmazonDynamoDBConfig();
   clientConfig.RegionEndpoint = RegionEndpoint.EUWest2;
   AmazonDynamoDBClient dynamoDbClient = new AmazonDynamoDBClient(clientConfig);
   var response = dynamoDbClient.ListTables(new ListTablesRequest());
```
The error is:
Unable to get IAM security credentials from EC2 Instance Metadata Service.

Didier_Durand · Answer

Hi,

Did you check via  `aws sts get-caller-identity` (or equiv in your SDK language) under which id you were executing the dDnamoDB. GIven your error, it's probably not under the identity of the role that you have defined.

So, add `aws sts assume-role --role-arn ""` in your code prior to DDB calls and it should go through.

Best,

Didier

Oleksii Bebych · Answer

> I assume any instance in the same account can access the Dynamo table

No. You must apply IAM role (instance profile) to every particular EC2 instance

You can do it during instance creation or for existing EC2 instance

![Enter image description here](/media/postImages/original/IMmSy_PMKETUqC2s9DjrvnRg)

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/iam-roles-for-amazon-ec2.html

iBehr · Answer

Ensure that the subnet in which your instance sits has either internet access (IGW in the route table) or a gateway endpoint for DynamoDB in the route table.

This link has the details on the Gateway Endpoint for Dynamo.
https://docs.aws.amazon.com/vpc/latest/privatelink/vpc-endpoints-ddb.html

Hope this helps!

Connect EC2 to DynamoDB

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